Additional file 2.

Additional Figure 1. TIV-specific IgG memory B cell frequency. Total B cells were isolated at baseline and one and six months following immunization
with 2006/2007 through 2009/2010 trivalent influenza vaccine (TIV), cultured with
CpG and IL-2 for four days, and TIV and total IgG specific EliSpots performed to determine
the frequency of TIV specific memory B cells. An individual subject may have provided
data from multiple study years. No statistical difference (P < 0.05) was detected among groups at individual time points.